# Relationship history for MSHA mine 2901802

Current hierarchy: **Leonard  Jensen → Leonard Jensen → W D Ranch Mines**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Mina Amigos Mining Company → W D Ranch Mines; 1980-01-01 to 1988-09-25; source msha-controller-operator-history
- **controller_controls_mine:** Holliday Ira → W D Ranch Mines; 1980-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holliday Ira → Mina Amigos Mining Company; 1980-01-01 to 1988-09-25; source msha-controller-operator-history
- **operator_operates_mine:** Leonard Jensen → W D Ranch Mines; 1988-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Leonard  Jensen → W D Ranch Mines; 1988-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Leonard  Jensen → Leonard Jensen; 1988-09-26 to current/open; source msha-controller-operator-history